I don't know if the physics are realistic, but Elite: Dangerous is the closest thing to a space flight simulator. Distance wise it's realistic at least, in that even with FTL speeds going 300x the speed of light you take forever to get to another planet.
The flight model in Elite is very much tuned for fun rather than accuracy. You can if you wish turn on a kind of newtonian physics flight model, but even then I very much doubt its representative of how actual objects in space would react.
